PET Scans for Early Alzheimer's Detection Might be Available Next Year

Positron emission tomography (PET) scans, a form of molecular imaging that detects beta amyloid plaques in the brain, may be available for use in the early detection of Alzheimer's disease in as few as 12 months, according to researchers presenting this week at the Society of Nuclear Medicine (SNM) 58th Annual Meeting in San Antonio.

“From a macro perspective, amyloid imaging with PET scans can help to ascertain the likelihood that individuals will deteriorate cognitively within a few years, thereby enabling more efficient channeling of healthcare resources,” said Kevin Ong, MD, lead author of a presented study and a research scientist at Austin Hospital, Melbourne, Australia. “From a micro perspective, planning and lifestyle modifications are possible for individuals who seek screening for Alzheimer's disease.”

Researchers have warned that the beginning stages of Alzheimer’s can precede symptoms of dementia by as much as a decade or more. Beta-amyloid accumulates as neurotoxic plaque in individuals preceding the onset of Alzheimer's disease, thereby compromising the neural tissues that control major mental and physical functioning—including memory, language and motor function.

“For individuals who have already developed a measurable memory decline, a positive scan for amyloid is the most accurate predictor of progression to Alzheimer's disease,” said Christopher Rowe, MD, a lead investigator for the Australian Imaging, Biomarkers and Lifestyle study of aging and professor of nuclear medicine at Austin Hospital, Victoria, Australia.

Three ongoing studies presented at this year’s SNM meeting show that amyloid plaques build up slowly, by an estimated two to three percent per year, and that they are often already present in healthy older individuals—12 percent of those in their 60s, 30 percent of those in their 70s and 55 percent in those over the age of 80. In one study, about 25 percent of subjects over the age of 60 had amyloid plaques.